How widespread actually is fingerprinting/tracking in practice? For example, if you visit a news site and a random forum about cars, who/how are the analytics linked together?

Most sites I see just use google-analytics for tracking but if that's disabled through ad-blocker, is cross-site tracking still a concern?

Even if you disable all javascript, (I understand that makes you stand out) sites still log your IP address and user-agent, which could be enough to track you? But its not like different sites actually send these logs to a central entity to link together your activity right?

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